OWASP Mobile Top 102024Rank #4Last reviewed 2026-07-27

M4:2024: Insufficient Input/Output Validation

Missing or weak validation of input from the network, deep links, IPC, or the user, and of output passed to native code, web views, or backend APIs.

How it's found

Identified by fuzzing app inputs and deep links for injection and improper output handling passed to native or web views.

Standards mapping

CWE: CWE-20 CWE-79 CWE-89
References: https://owasp.org/www-project-mobile-top-10/2023-risks/m4-insufficient-input-output-validation.html

Where this fits in a TurboPentest engagement

This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.

Frequently asked questions

What is M4:2024 Insufficient Input/Output Validation?

Missing or weak validation of input from the network, deep links, IPC, or the user, and of output passed to native code, web views, or backend APIs.

How do you find Insufficient Input/Output Validation?

Identified by fuzzing app inputs and deep links for injection and improper output handling passed to native or web views.

Which CWEs map to M4:2024?

M4:2024 maps to CWE-20, CWE-79, CWE-89.

Does TurboPentest test for Insufficient Input/Output Validation?

This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.

Related OWASP categories

Written and reviewed by

Michel Chamberland - Founder & CEO, IntegSec

CISSP, OSCP, OSCE, CEH, GIAC, CCSK · 20+ years in offensive security

Michel has spent 20+ years on offensive security teams including IBM X-Force Red and Trustwave SpiderLabs, leading penetration tests, red team engagements, and breach response for Fortune 500 customers. He is the founder of IntegSec and the architect of TurboPentest.

Find these issues before an attacker does

TurboPentest runs an agentic AI pentest against your target and reports findings with proof, from $99 per target.

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OWASP Mobile Top 102024Rank #4Last reviewed 2026-07-27

M4:2024: Insufficient Input/Output Validation

Missing or weak validation of input from the network, deep links, IPC, or the user, and of output passed to native code, web views, or backend APIs.

How it's found

Identified by fuzzing app inputs and deep links for injection and improper output handling passed to native or web views.

Standards mapping

CWE: CWE-20 CWE-79 CWE-89
References: https://owasp.org/www-project-mobile-top-10/2023-risks/m4-insufficient-input-output-validation.html

Where this fits in a TurboPentest engagement

This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.

Frequently asked questions

What is M4:2024 Insufficient Input/Output Validation?

Missing or weak validation of input from the network, deep links, IPC, or the user, and of output passed to native code, web views, or backend APIs.

How do you find Insufficient Input/Output Validation?

Identified by fuzzing app inputs and deep links for injection and improper output handling passed to native or web views.

Which CWEs map to M4:2024?

M4:2024 maps to CWE-20, CWE-79, CWE-89.

Does TurboPentest test for Insufficient Input/Output Validation?

This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.

Related OWASP categories

Written and reviewed by

Michel Chamberland - Founder & CEO, IntegSec

CISSP, OSCP, OSCE, CEH, GIAC, CCSK · 20+ years in offensive security

Find these issues before an attacker does

TurboPentest runs an agentic AI pentest against your target and reports findings with proof, from $99 per target.

Start a pentest